Analytical Study of Hybrid Techniques for Image Encryption and Decryption

Area of Science:

• Computer Science
• Cryptography
• Digital Image Processing

Background:

• Image encryption is crucial for digital media security.
• Existing research often focuses on Advanced Encryption Standard (AES).
• Hybrid approaches combining symmetric and asymmetric cryptography offer enhanced security and efficiency.

Purpose of the Study:

• To analyze and compare hybrid image encryption techniques.
• To evaluate the performance of Elliptic Curve Cryptography (ECC) with Hill Cipher (HC), ECC with AES, and ElGamal with Double Playfair Cipher (DPC).
• To assess security and efficiency metrics for various hybrid cryptosystems.

Main Methods:

• Hybridization of asymmetric cryptosystems (ECC, ElGamal) with symmetric cryptosystems (HC, AES, DPC).
• Performance evaluation based on encryption/decryption time, image entropy, intensity loss, PSNR, NPCR, and UACI.
• Comparative analysis of different hybrid cryptographic combinations.

Main Results:

• ECC with AES is suitable for remote communications with smaller images due to encryption/decryption time.
• ECC with HC demonstrates a good overall performance for image encryption based on metric measurements.
• Hybrid methods leverage the speed of symmetric algorithms and the security of asymmetric algorithms.

Conclusions:

• Hybrid cryptosystems offer a balance between speed and security in image encryption.
• The combination of Elliptic Curve Cryptography and Hill Cipher presents a promising solution for image encryption.
• Further research can explore other hybrid combinations for optimized image security.